61609984 has 48 divisors (see below), whose sum is σ = 125307000. Its totient is φ = 30277632.

The previous prime is 61609979. The next prime is 61609991. The reversal of 61609984 is 48990616.

It is a self number, because there is not a number n which added to its sum of digits gives 61609984.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 136992 + ... + 137440.

Almost surely, 2^61609984 is an apocalyptic number.

61609984 is a gapful number since it is divisible by the number (64) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 61609984, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (62653500).

61609984 is an abundant number, since it is smaller than the sum of its proper divisors (63697016).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

61609984 is an equidigital number, since it uses as much as digits as its factorization.

61609984 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 538 (or 518 counting only the distinct ones).

The product of its (nonzero) digits is 93312, while the sum is 43.

The square root of 61609984 is about 7849.2027620644. The cubic root of 61609984 is about 394.9575001008.

The spelling of 61609984 in words is "sixty-one million, six hundred nine thousand, nine hundred eighty-four".